PDS Tornado Watch – 2011 Super Outbreak – Northern AlabamaURGENT – IMMEDIATE BROADCAST REQUESTED TORNADO WATCH NUMBER 235 NWS STORM PREDICTION CENTER NORMAN OK 145 PM CDT WED APR 27 2011 THE NWS STORM PREDICTION CENTER HAS ISSUED A TORNADO WATCH FOR PORTIONS OF MUCH OF ALABAMA NORTHWEST GEORGIA SOUTHEAST MISSISSIPPI SOUTHERN MIDDLE TENNESSEE EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 145 PM UNTIL 1000 PM CDT. …THIS IS A PARTICULARLY DANGEROUS SITUATION… DESTRUCTIVE TORNADOES…LARGE HAIL TO 4 INCHES IN DIAMETER… THUNDERSTORM WIND GUSTS TO 80 MPH…AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 80 STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES NORTHEAST OF HUNTSVILLE ALABAMA TO 60 MILES WEST SOUTHWEST OF EVERGREEN ALABAMA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5). REMEMBER…A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS. OTHER WATCH INFORMATION…CONTINUE…WW 230…WW 231…WW232…WW 233…WW 234… DISCUSSION…A CLASSIC TORNADO OUTBREAK SITUATION IS DEVELOPING ACROSS MUCH OF AL AS DISCRETE TORNADIC SUPERCELLS FORM OVER MS AND TRACK ACROSS THE WATCH AREA. STRONG LOW LEVEL AND DEEP LAYER VERTICAL SHEAR…COMBINED WITH A MOIST AND MODERATELY UNSTABLE AIR MASS…WILL POSE A DANGEROUS RISK OF STRONG/VIOLENT AND POTENTIALLY LONG-TRACK TORNADOES. AVIATION…TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 4 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 25040.Storm Prediction Center – Public Domain
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